When to Call Local Flood Repair Experts — and What They Actually Do

A pipe or supply line lets go

The most common serious loss in an American home is a supply line under pressure that fails — a pipe in a wall, a braided line under a sink, the hose behind the washing machine. Because it is under pressure, it does not drip; it sprays, often for hours before anyone is home to notice.

Do three things in order. Shut the water at the fixture's angle stop, or at the main if you cannot reach it. Kill power to the affected area at the breaker if water is anywhere near outlets or the panel. Then start moving water out and lifting contents up onto blocks. This is clean, Category 1 water — the good version — but only while it is fresh. Sitting against drywall and subfloor in a warm house, it degrades within a day or two, and a Category 1 loss that waited a weekend is no longer a Category 1 loss.

Photograph everything before you move it, including the failed part itself. That part is your evidence that this was sudden and accidental rather than a slow leak you ignored, and that distinction is the whole ballgame on the claim.

An appliance is the culprit

Water heaters, washing machines, dishwashers and refrigerator ice-maker lines cause a steady share of household losses, and they share a trait: they fail quietly, often into a space you don't look at — behind, beneath, inside a cabinet.

A water heater is the one to respect. They last eight to twelve years, they do not fail gracefully, and forty gallons on a floor is a bad afternoon. Know its age, keep a drain pan under it, and replace it on schedule rather than on failure. A dishwasher or washing-machine discharge is often Category 2 grey water — mild contamination — which changes what can be salvaged: carpet pad usually goes, and porous materials get scrutinised rather than assumed dry.

The hidden-cabinet problem is why these get expensive. Water wicks into the cabinet base, the subfloor and the wall behind before anything shows on the surface, so by the time you see it the wet area is larger than it looks. A moisture meter in the hands of someone who knows where to scan finds the real edge of the loss, which is never where the visible edge is.

Sewage backs up

A sewer or septic backup is not a bigger version of a clean-water loss. It is a different category of problem — Category 3, black water — and it is the one scenario in this guide where the honest advice is to stop and call, not to start mopping.

Black water carries bacteria and pathogens, and the rules change accordingly: porous materials that got wet are removed, not dried. Drywall, insulation, carpet, pad, particle board — out. The people doing it wear real protective equipment and work behind containment, for reasons the OSHA's flood-cleanup hazard guidance and the CDC's floodwater safety guidance both spell out plainly.

Two practical notes. First: standard homeowners policies usually exclude sewer backup unless you bought the endorsement — it is cheap, often capped at $5,000–$10,000, and worth having before you need it. Second: keep people and pets away from it entirely. This is the loss to be conservative about, because the downside is health, not just drywall.

A storm gets in through the roof

Wind lifts shingles, a branch punches the roof, hail opens seams — and the next rain comes inside. Storm intrusion has a wrinkle the others don't: the coverage often depends on sequence. Wind or hail damages the roof, and rain then enters through the opening the storm made — that is generally covered. Rain that simply found a pre-existing gap you hadn't maintained generally is not.

Which makes documentation of the storm itself matter as much as documentation of the water. Photograph the roof damage, the entry point and the interior, and get a tarp over the opening fast — you have a duty to prevent further damage, and a carrier can decline the part of the loss your delay caused. Ready.gov covers the immediate-safety side.

Note also what storm water is not: if water rose from the ground and came in low, that is flood, and it lives under a different policy entirely — the next scenario.

Actual flood — water that came from the ground up

The word "flood" has a specific meaning that catches people at the worst possible time. Water that rises from outside and touches the ground before it reaches your house is flood, and a standard homeowners policy does not cover it — regardless of how the water got there, storm or not.

Flood is a separate NFIP flood policy. It carries a 30-day waiting period, so it cannot be bought once the forecast turns, and roughly a quarter of NFIP claims come from outside designated high-risk zones — which is why "I'm not in a flood zone" is not the reassurance people think it is. Check the actual map for your address at the FEMA Map Service Center before concluding anything.

Flood water is also, almost always, contaminated — it ran across ground, roads and whatever was in its path — so it is treated like Category 3: porous materials out, health precautions in. The restoration work resembles the sewage scenario more than the clean-pipe one, even though it arrived as weather.

The basement takes on water

Most "mystery" basement water is not a mystery to anyone who looks outside. It is a downspout dumping roof runoff against the foundation, or grading that slopes toward the house instead of away, or a window well with no drainage. The water you see inside is a symptom; the cause is usually a few feet up and to the left, outdoors.

Fix the outside first, because a dry-out that ignores the source just runs again next storm. Extend downspouts well away from the wall, correct the grade so the ground falls away from the foundation, and clear the window wells. Inside, a sump pump earns its keep — but only if it works, which is why you test it before the season and add a battery backup, because the power fails during precisely the storm you need it for.

Groundwater seepage is also the classic slow loss that becomes a mould problem rather than a flood: a little water, often, into an unventilated space full of stored cardboard and fabric. The EPA's mould guidance threshold is the one to remember — small and caught is a DIY job, large or persistent is a contractor.

The leak you can't see

A slab leak under the foundation, a supply line inside a wall, a shower pan seeping into the subfloor — these are the losses that do the most damage per gallon precisely because nothing dramatic happens. The tells are indirect: a warm spot on the floor, a water bill that climbed for no reason, a musty smell with no visible source, paint that bubbles or a baseboard that cups.

Two things make hidden leaks their own category. First, they are found with tools, not eyes — thermal imaging and moisture meters trace water back through materials to a source no one can see, which is a real skill rather than a guess. Second, and painfully, they are the losses most likely to be denied: a policy's "seepage or leakage over 14 days" exclusion means a slow leak you genuinely could not have found can still be excluded, even when the damage is severe and you did nothing wrong.

Which is why, on a hidden leak, the documentation of when you discovered it and what you did next matters more than on any other loss. Report promptly, mitigate immediately, and keep the timeline clean.

What the crew actually does when they arrive

Whatever the cause, a competent restoration response looks broadly the same, and knowing the shape of it tells you whether the people in your house are doing the job or performing it.

They inspect and classify first — category of water, class of loss, extent — because that decides everything downstream. They take moisture readings on day one and set a dry standard from an unaffected area to measure against. They extract standing water, then remove what cannot be saved. Then they set drying equipment sized to the space, not to what happened to be on the truck, and they come back daily to read moisture and adjust.

The single most useful thing you can ask for is the daily moisture log. A real crew keeps one as a standard deliverable and hands it over without hesitation; its absence tells you they are drying by calendar rather than by measurement. The IICRC certifications (WRT, ASD, AMRT) are the credential behind all of this, and the S500 standard is the standard it follows.

Why drying takes days, not hours

Homeowners see fans and assume it is a speed problem: more air, done sooner. It is closer to a chemistry problem. Water leaves a material only into air that is drier than the material, and stays gone only if that humid air is pulled out of the building rather than pushed into the next room.

So a real dry-out runs two machines together. Air movers break the layer of saturated air sitting on wet surfaces and force evaporation. Dehumidifiers pull that moisture out of the air and drain it away. Fans alone just relocate the humidity — which is how an enthusiastic DIY dry-out grows mould in a wall that was never wet to begin with.

Typical structural drying runs three to five days; concrete, plaster and hardwood take longer. The equipment is loud and runs around the clock, and turning it off overnight because you cannot sleep restarts the whole clock. Readings, not the calendar, decide when it comes out — so if someone declares it dry on day two without showing you a number, they are describing their schedule, not your building.

The mould window, stated honestly

Every restoration outfit quotes "mould grows in 24 to 72 hours," and it has hardened into a sales line. The real claim is narrower and conditional: given moisture, an organic food source and normal room temperature, visible growth can begin in that window. The EPA's mould guidance puts the practical threshold at 24 to 48 hours for wet materials.

Conditional is the operative word. A cool basement grows slower; a warm, closed-up house in summer is a growth chamber. Drywall paper, wood and ordinary dust are all food; glass and steel are not. Spores are already in your home today, harmlessly — moisture is the one variable you actually control, which is why every real remediation guideline is a moisture-control guideline underneath.

Scale decides who does the work: the EPA's cleanup guidance draws the line near ten square feet. Below it, a homeowner in a mask usually manages. Above it, or with any HVAC involvement, you want containment and a professional. And read the CDC's mould and health page, which is deliberately more measured than the remediation industry's marketing — it does not support the "toxic black mould will destroy your family" framing used to sell whole-house jobs.

What you should be holding when it's over

The job is finished when you have the documentation, not when the fans leave — because in six months the documentation is the only part that still exists. Ask for all of it up front, because a crew that knows on day one you expect a moisture log tends to keep a better one.

• The daily moisture log — readings per material against a dry standard, proving the building reached dry rather than reached Friday.
• Before/during/after photos, including what went back behind the walls you'll never see again.
• A line-item invoice matching the agreed scope, with changes explained rather than absorbed.
• A certificate of completion — often what your carrier wants before it releases final payment.
• The warranty in writing, with a duration and a name on it.
• Any lab results if mould was tested — and remember the firm that tests should not be the firm that remediates.

On the claim itself: report promptly, keep every receipt including the fans you rented at 2am, compare estimates by line-item scope rather than by total, and don't sign an assignment of benefits in the first hour. If it stalls, your state insurance department and the Insurance Information Institute are where the homeowner side of the argument lives.